In a gasoline station, there is an underground gasoline storage tank for supplying gasoline dispensers ("pumps"). The storage tank is periodically refilled from a gasoline tanker. This refilling process is accomplished by means of a hose connected to the tanker at one end and having a nozzle inserted into a nozzle adaptor at the top of a fill pipe or riser leading to the underground storage tank. Typical adaptors, as made by Emco Wheaton and other companies, are threaded to the top of the fill pipe.
Periodically, these adaptors are found to be lose, e.g., by an environmental official or inspector who can fine the station owner for this hazardous condition. It has been discovered that this loosening of the adaptor sometimes occurs as a result of the refilling process. That is, when the tanker finishes pumping gasoline into the fill pipe, there is still a substantial amount of gasoline in the hose connected to the tanker. The operator typically picks up the hose at the tanker, holds the hose up, and walks towards the fill pipe causing the excess gasoline in the hose to flow into the fill pipe, This works well to avoid spilling or wasting gasoline, but the hose acts as a lever and often rotates and/or loosens the threaded adaptor.
What is needed is a way of preventing loosening of the adaptor to avoid such a hazardous condition and the costs of spilled gasoline creating a fire hazard and causing contamination.